Case Series: Intrathecal Baclofen Therapy in Stiff-Person Syndrome

Stiff-person syndrome (SPS) is associated with axial rigidity superimposed on sustained muscle spasms. These symptoms commonly interfere with the performance of activities of daily living including ambulation. This retrospective case series evaluates the outcomes of screening tests and chronic infusion of intrathecal baclofen (ITB) in patients diagnosed with SPS treated in our spasticity clinic.

Patients were identified from an institutional review board-approved clinical registry of ITB therapy. Data from clinical encounters were extracted from the registry and from the patients' electronic medical record. All patients with medically refractory spasticity related to SPS screened with an ITB injection were included. In addition to pertinent demographic and clinical information, data from validated outcome measures routinely used in the clinic were collected: pain Numeric Rating Scale, Spasm Frequency Scale, lower extremity Modified Ashworth Scale (MAS), and Timed 25 Foot Walk. Outcomes data for chronic ITB infusion were assessed at early (<6 months) and late follow-up (6-12 months) visits after surgery.

Nine patients were included, and seven received chronic ITB infusion. MAS scores were improved at early and late follow-up, and five patients experienced a reduction in pain scores. Walking performance remained stable in previously ambulatory patients. Four patients experienced complications related to ITB implantation, which resolved with medical or surgical treatment.

Consistent with other case series, our results suggest that ITB is an effective therapy for medically intractable spasticity due to SPS, and symptom reduction can be achieved without compromising ambulation.